It may be another year before a standard for the new higher speed 56 Kilobit-per-second (Kbps) modems is agreed, but Compaq Computer Corp and modem manufacturer Hayes Microcomputer Products have shown they are determined to have their say: they have announced plans to ship products based on the K56flex protocol by the end of the first quarter this year. K56flex is the software protocol which is being developed by the Microelectronics group of Lucent Technologies Inc and Rockwell Semiconductor Systems, part of Rockwell International Corp. Rockwell and Lucent announced in November last year an agreement to make their technologies compatible. Lucent says the new technology will connect personal computers to the Internet over regular analog phone lines at almost twice the speed of today’s typical modems, the fastest of which clock in at around 33.6 Kbps. But the problem with trying to speed up modems is that you can’t receive data at 56 kbps if your Internet Service Provider is sending it to you at 28.8 Kbps – hence the need for a standard which the Internet service providers would be confident to adopt.
Almost full duplex
Until now it wasn’t just the service providers which could have held up 56 Kbps modems, as the manufacturers have struggled to achieve high baud rates if the communication is two-way – known as full duplex – with the current available network infrastructure. In other words the modems would be fine if communication is one-way – which the Internet predominantly is – but wouldn’t speed things up much for a two-way use like video- conferencing. While Lucent and Rockwell are not actually describing the new protocol as offering full duplex, they do claim that it offers high speeds bi-directionally. The other modem company hoping to affect a 56 Kbps modem standard is the Semiconductor arm of US Robotics. Perhaps feeling a little left out in the cold since the Lucent-Rockwell cozy-up, the company claims its modems achieve higher speed through software, so upgrades to conform with any official standard could be carried out quickly and easily. The principle behind all three technologies is the same – traditional modulation techniques, designed for long distances over poor-quality lines, are not absolutely necessary for Internet access, where for most users the only analogue portion of the call is from the user to a local phone company switch. The analog-to-digital conversion only needs to be performed once; and this, combined with the introduction of new encoding techniques, means that 56Kbps should now be possible. But if the drive to affect the standard seems complicated, that’s because it is: US Robotics has signed up Lancaster, Pennsylvania-based Cardinal Technologies Inc and Cirrus Logic Inc, as well as more than 30 Internet service providers, including America Online Inc, IBM Corp’s Global Network arm and MCI Communications Corp. Ascend Communications Inc and Shiva Corp have announced plans to use Rockwell’s technology, and Microcom Inc is collaborating with Rockwell to develop a high-speed protocol. Late last year, Lucent struck a deal with 3Com Corp under which 3Com will offer users of its AccessBuilder 8000 remote access concentrator line a software upgrade enabling it to communicate with modems using the Lucent V.Flex2 technology – potentially bringing it millions of users (CI No 3,054). Personal computer modem pioneer Hayes had said that it was holding back any 56 Kbps products until an official standard is released, but this latest announcement shows that the company couldn’t resist putting its oar into the modem standards water.
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